Had been with a firm for years, doing everything but signing the cheques, suddenly told that I was being laid off in 6-weeks.
Those 6-weeks were fascinating. The owners kept watching me like a hawk obviously expecting me to slack off or misbehave or something. They took less time away in those 6-weeks than the previous 6-months, they were so busy watching me.
I behaved exactly as I ever had. In early, stayed until day's work was done, didn't even mention to anyone outside company that I would be leaving. I did have all sorts of fantasies of how I could 'stick it to them' but couldn't bring myself to do anything but my job as best I could.
The weekend after I left I met a friend of the owners who kept looking at me strangely. Asked him what the problem was and he told me that my ex-employers were going around telling everyone how strange I was: that they had canned me and I hadn't gotten upset or reacted at all as they had expected.
Several years later met him again. He said they still brought up my 'strange' behaviour. Apparently my (in)action bothered them far longer than their action bothered me.